Road sanding machine



1959 M. F. SMITH 2,907,482

ROAD SANDING MACHINE Filed July 30, 1957 5 Sheets-Sheet 1 fNVENTOR. INOT F. SMITH U Q N Oct. 6, 1959 M. F. SMITH 2,907,482

ROAD SANDING MACHINE Filed July 30, 1957 5 Sheets-Sheet 2 RT 'm ow INVENTOR. MINOT F. SMITH ATTORNEYS gg 0%, yfiawmfm Oct. 6, 1959 M. F. SMITH 2,907,482

. ROAD SANDING MACHINE Filed July 30, 1957 5 Sheets-Sheet 3 MINOT F. SMITH w,% gamfi5mfow ATTORNEYS ,A INVENTOR.

Oct. 6, 1959 M. F. SMITH 2,

ROAD SANDING MACHINE Filed July 30, 1957 5 Sheets-Sheet 5 INVENTOR. MINOT F. SMITH w v ATTORNEYS ROAD SANDING MACHINE Minot F, Smith, Wellesley Hills, Mass, assignor to Underwood Machinery Company, Somerville, Mass., :1 corporation of Massachusetts Application July 30, 1957, Serial No. 675,105

3 Claims. (Cl. 21483) The present invention relates to machines for distributing sand over the surface of icy or otherwise slippery roads. Heretofore in order to have the sand distributed ahead of the rear wheels and in both lanes of the road, it has been customary either to arrange the truck so that there is more of the load on one side of the center line of the'chassis than on the other, or, to avoid this serious objection, the longitudinal conveyor has been placed centrally and a transverse conveyor has been provided to carry sand from the center conveyor crosswise of the truck to the sand-spreading apparatus. Such machines are subject to serious defects, one being that, if the sand is sticky or wet and especially in cold weather, if it contains salt or calcium chloride, it is likely to arch and fail to drop into the open top of the conveyor trough with the result that the feed is irregular or stops altogether. Frequently it has been necessary to have a man push the sand down from time to time to, make sure that it feeds. This Work is dangerous and has resulted in the loss of more than one life. Such machines have sometimes been provided with power-operated agitators in the body above the conveyor trough to avoid the necessity of pushing .down the 'sand by hand but they are costly, both to build and to operate. 7

Accordingly one object of the present invention is to provide a truck body in which the sand will not arch and interfere with the feed, and yet will not press down so hard on the conveyor as to interfere with the operation of the conveyor, particularly when the load has stood for some time and packed down in open top of the conveyor trough. No agitator or stirrer mechanism is required and yet the feed is certain and uniform, the weight of the body reduced and consequently its sand-carrying capacity materially increased. This is accomplished by taking advantage of the known fact that sand or the like will arch if both sides of a bin are inclinded but will not if one is substantially vertical while the other is inclined, and this is true even if the sand or the like is damp or sticky. This action is explained by the fact that the sand which is in contact with the substantially vertical side of the bin is free to move downward when its support is removed and the downward movement of this sand takes away the support from the sand resting on the inclined wall so that it moves downward with the sand which is in contact with the vertical wall.

Also, in the road sanding machine embodying my invention the load is uniformly distributed with respect to the longitudinal axis of the truck.

The sander body embodying my invention requires no changes in the truck chassis but can be placed on any standard chassis of the right size. While I have shown herein sand spiea'ders of the type which I prefer to use, the invention is not limited to Spreaders of this particular type.

In the drawings:

Fig. 1 is a top plan view of a sand truck embodying my present invention. 1

Fig. 2 is a vertical section of the body looking in the direction of the arrows, on line 2--2 of Fig. 1.

Fig. 3. is a vertical section on line 33 of Fig. 1, lookto the rear, r r i nited States Patent ICC Fig. 4 is a vertical section on line 4--4 of Fig. 1, looking to the rear.

Fig. 5 is an elevation of a portion of the front of the body showing the sand spreaders and the operating mechanism.

Fig. 6 is a vertical section on line 6--6' of Fig. 5.

Fig. 7 is an elevation of the sand-spreading mechanism taken from the rear.

Fig. 8 is a plan view of a portion of the feed conveyor.

Fig. 9 is an end elevation of the feed conveyor and trough.

By way of introduction to the'more detailed description of the invention, it may be said that, at the bottom of the body and resting on the chassis frame, there is an open top conveyor trough A extending diagonally from the right rear corner to the left front corner; that the sand spreader B is at the front end of the trough outside of the chassis frame and ahead of the rear wheels; that there is a rectangular hopper C with sloping sides forming the top of the body; that beneath the hopper is an intermediate exterior rectangular body portion D, and that inside of this is an interior body portion composed of sloping plates connecting the rectangular lower perimeter of the hopper with the upper edge of the open diagonal conveyor trough A.

Referring now more particularly to the drawings, at 20, is shown the chassis frame and at 21 the rear wheels and at 22 the cab. The lower part of the body is con structed with a vertical front wall 34 which is next to the cab, vertical outer lengthwise side walls 35, 35 and a vertical rear wall 36 which extends only part way up the body. These walls 34,135, 35 and'36 together form the intermediate exterior rectangular body portion D. Above the body D and resting on it, is the hopper C composed of sloping sides 39 and 40 and a sloping rear plate 38 which is part of the vertical rear wall 36 already described. The intermediate exterior rectangular body portion D supports the weight of the hopper C and the load of sand carried by the truck.

On the outside of the body is a series of triangular braces 41 which tend to stiffen the lower portion of the body and support the hopper C. Resting on the chassis frame 20 of the truck is the open top conveyor trough A which is conveniently in the form of a half-octagon in cross section (see Figs. 3, 4 and 5). This conveyor trough A extends diagonally from the right-rear'corner of the body to the left-front corner and contains a feed conveyor 25 comprising a shaft 26 provided with vanes or blades 27 shaped in the well known manner and acting to cause the sand in the trough to be urged forward along the trough.

Accordingly, sand from the hopper which falls into the conveyor trough 24 is moved forward lengthwise of the conveyor trough from the rear to the front and emerges at the front end of the conveyor trough. I In practice I extend the conveyor trough A for a little way forward of the front wall 34 of the body so that the sand, if very dry, will not flow out of the end of the trough and through the sand spreader B when the spreader is not in use and be wasted.

The exterior body portion D on which rests the hopper 40 is provided with lining plates or false walls 43, 44 which rise from the edges of the conveyor trough A and join the lower edges of the hopperC and serve to direct the sand into the open top of the conveyor trough A. Since thelower perimeter of the hopper C is symmetrical with the axis of the chassis indicated by line F-F in Fig. 1, and since the axis of the conveyor trough A is diagonal to it, and since the conveyor trough A is constructed to extend ahead of and slightly to one side of the front. plate 34 of the body as shown at 42 in Fig. 1,

3 the interior or lining plates 43, 44 are shaped so that they form smooth guiding surfaces leading from the bottom of the hopper C to the conveyor trough A. Taken together these lining plates 43, 44 constitute what is conveniently calledthe interior body portion designated E in the drawings. At the rear of the body and on the right-hand side the lining plate 43 is substantially vertical (see Fig. 3) while the wall 44 on the left-hand side slopes down continuously from the bottom of the hopper C to the upper edge of the conveyor trough A. At the front ofth'e body the side wall 35 is cut away to permit the conveyor trough A to emerge and extend outward beyond the lane of the body wall 35 and forward of the front wall 34. The lining plate 44 on the other side, i.e., the right side of the conveyor trough A is sloped to meet the edge of the conveyor trough. Therefore the interior of the body below'thelower edge of the hopper will feed the sand downward into the conveyor trough A although it is placed diagonally of the body.

Inside the body and extending from the lining plate 43 on one side across and above the conveyor trough to the lining plate 44 on the other side are three baffles which also serve as braces to stiffen the body. Two of these designated 46 are substantially flat plates bent slightly upward and secured to the lining plates while the third 47 or middle baffie is a plate which is V-shaped in cross section and having its upper ridge on a level with the lower edges of the hopper. These braces not only strengthen the body but also take some of the downward pressure of the sand, which otherwise, particularly when the truck has, stood loaded for some time, may pack into the discharge conveyor so tightly that its moving member can be started in motion only with great difficulty and may be broken if power enough is applied to start it in spite of the resistance of the closely packed sand. In other words, my sloping wall construction prevents'arching so effectively that under some conditons it is desirable to counteract it to some extent and'cause arching by the baffles over a part of the length of the trough, thereby reducing the strain on the moving member of the conveyor when it is started.

The drive mechanism for my improved sander includes an engine or motor 48, a clutch and a shaft 50 and sprocket wheel 51, all indicated in dash lines in Fig. l. A roller chain 52 passes around this sprocket and around a sprocket 53 on the rear end of the conveyor shaft 26 already described. A tightening sprocket 54 to control the tension on the chain 52 is also provided. The motor or engine 48 is controlled by suitable mechanism (not shown) in the cab 22.

The front end of the conveyor trough A extends forward past the front vertical body wall 34 into a housing 55 down which the sand falls as it is pushed forward by the blades 27 on the conevyor shaft 26. The lower end of this housing 55 is formed into two compartments 56 and 57 (see Fig. 7) into which the sand is fed. The forward compartment is designated 56 and the rear one 57. A swinging vane 58 pivoted at 59 which can be swung from side to, side is shown by the dot-dash lines in Fig. 5. Two sloping deflectors 60 and 61 cooperate with the vane 58 and direct the sand as it emerges from the conveyor; When the 'vane 53 is swung to the left against de- 7 flector 60 as shown in Fig. 5, the sand from the conveyor passes into the front compartment 56 and when it is swung to the right against deflector 61 it passes into the rear compartment 57. Under these circumstances all of the sandisthrown onto one side of the road or the other according .to the position of the vane. When the van'e'is in the middle position the sand is supplied simultaneously to both sand compartments, and hence will be spread on both sides of the road.

The sand spreader 'withtwo compartments is con- .Structed in accordance with the prior patent to Frank Underwood No. 2,738,195, March 13, 1956.

The sand SPI'fifldfllS' are provided with rapidly rotating disks 62 and 63 contained in casings 72 or 73 respectively having blades or projections 64. These casings have openings 74, respectively in the bottom through which the sand is projected by the sander disks 62 and 63. The front sander disk 62 is mounted on shaft 65 carrying a sprocket wheel 66 around which passes a chain 67 which also passes around another sprocket wheel 68 on the front end of conveyor shaft 26. The front sander disk shaft 65 is provided with'a gear 69 which meshes with a gear 70 of equal size on a shaft 71 which carries the back sander disk 63. Consequently the back sand spreader 63 is driven at the same speed as the front sand spreader disk 62 but in the opposite direction and the sand from the two sand spreaders are thrown sidewise of the road but in opposite directions.

Therefore, the construction of my improved sander is such that the truck carrying the sanding machine may proceed along either lane of the road and simultaneously sand the lane it is in and the other lane. Thus it can travel with the trafiic while sanding either or both lanes.

I claim:

1. A body for a sander truck including an upwardly open conveyor trough at the bottom of said body extending from the rear corner on one side of the diagonally opposite corner on the other side, a conveyor located within said trough for conveying the contents of the body, the lower edges of the side walls of said body above said conveyor trough joining the upper edges of the side walls of said trough along the length thereof, said body having a discharge opening to Which said conveyor extends for removing the contents from the body, at least a portion of one of said side walls of said body adjacent the discharge opening and adjacent the upper edge of said trough to which it is joined depending downwardly in a generally vertical direction and the portion of the opposite side wall of said body opposite said first mentioned portion of said one side wall being sloped with respect to said first mentioned portion.

2. A body according to claim 1, at least a portio of said opposite side wall adjacent the end of said body opposite said discharge opening and adjacent the upper edge of the trough to which it is joined depending downwardly in a generally vertical direction and the portion of said one side wall opposite said last mentioned of said opposite side Wall being sloped with respect to said last mentioned portion.

3. A body for a sander truck including an upwardly open conveyor trough at the bottom of said body extending from the rear corner on one side to the diagonally opposite corner on the other side, the top of said body being generally rectangular, a conveyor located within said trough for conveying the contents of the body, the lower edges of the side walls of said body above said conveyor trough joining the upper edges of the side walls of said trough along the length thereof, said hopper having a discharge opening to which said conveyor extends for removing the contents from the body, each of said side walls of said body above said trough from front to rear comprising portions of different slope'with adjacent portions coming together at an angle.

References Cited in the file of this patent UNITED STATES PATENTS 1,293,281 7 Wills .Feb. 4, 1919 1,915,758 Pierce June 27, 1933 2,705,149 Torrey Mar. 29, 1955 2,738,195 Underwood Mar. 13, 1 956 2,770,376 NOV. 13, FOREIGN PATENTS 514,866; Canada July 19, 1955 

